The Director of the National Park Service is sending you the following
announcements and actions on properties for the National Register of Historic
Places.

Impact of Mail Irradiation Program on National Register Nominations

As you may be aware, the US Postal Service (USPS) intends to irradiate mail
in selected USPS facilities, including our mail facility here in Washington
D.C., to sterilize it from possible anthrax contamination using high-energy
electron irradiation technology. We have concerns about the possible effects of
irradiation on nominations to the National Register that pass through these
facilities. We are advising you to avoid using USPS for envelopes and flats
that contain National Register nominations, Determinations of Eligibility, and
any other material that will be archived here.

Paper will be seriously affected, losing tensile strength and increasing
brittleness. In addition to accelerating the aging processes, discoloration is
also to be expected. Oxidation is expected from the interaction with ozone
formed in air (and within the packages) during irradiation. Photographs will be
adversely affected as well. Magnetic media (floppy disks, zip disks, audio and
video tape) will probably lose significant information content.

We strongly recommend using an alternate shipper such as United Parcel
Service (UPS) or Federal Express (FedEx) for sending nominations to the
National Register of Historic Places. Use our physical location address only: